1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/fs/hpfs/name.c
4 *
5 * Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
6 *
7 * operations with filenames
8 */
9
10#include "hpfs_fn.h"
11
12static inline int not_allowed_char(unsigned char c)
13{
14 return c<' ' || c=='"' || c=='*' || c=='/' || c==':' || c=='<' ||
15 c=='>' || c=='?' || c=='\\' || c=='|';
16}
17
18static inline int no_dos_char(unsigned char c)
19{ /* Characters that are allowed in HPFS but not in DOS */
20 return c=='+' || c==',' || c==';' || c=='=' || c=='[' || c==']';
21}
22
23static inline unsigned char upcase(unsigned char *dir, unsigned char a)
24{
25 if (a<128 || a==255) return a>='a' && a<='z' ? a - 0x20 : a;
26 if (!dir) return a;
27 return dir[a-128];
28}
29
30unsigned char hpfs_upcase(unsigned char *dir, unsigned char a)
31{
32 return upcase(dir, a);
33}
34
35static inline unsigned char locase(unsigned char *dir, unsigned char a)
36{
37 if (a<128 || a==255) return a>='A' && a<='Z' ? a + 0x20 : a;
38 if (!dir) return a;
39 return dir[a];
40}
41
42int hpfs_chk_name(const unsigned char *name, unsigned *len)
43{
44 int i;
45 if (*len > 254) return -ENAMETOOLONG;
46 hpfs_adjust_length(name, len);
47 if (!*len) return -EINVAL;
48 for (i = 0; i < *len; i++) if (not_allowed_char(c: name[i])) return -EINVAL;
49 if (*len == 1) if (name[0] == '.') return -EINVAL;
50 if (*len == 2) if (name[0] == '.' && name[1] == '.') return -EINVAL;
51 return 0;
52}
53
54unsigned char *hpfs_translate_name(struct super_block *s, unsigned char *from,
55 unsigned len, int lc, int lng)
56{
57 unsigned char *to;
58 int i;
59 if (hpfs_sb(sb: s)->sb_chk >= 2) if (hpfs_is_name_long(from, len) != lng) {
60 pr_err("Long name flag mismatch - name ");
61 for (i = 0; i < len; i++)
62 pr_cont("%c", from[i]);
63 pr_cont(" misidentified as %s.\n", lng ? "short" : "long");
64 pr_err("It's nothing serious. It could happen because of bug in OS/2.\nSet checks=normal to disable this message.\n");
65 }
66 if (!lc) return from;
67 if (!(to = kmalloc(size: len, GFP_KERNEL))) {
68 pr_err("can't allocate memory for name conversion buffer\n");
69 return from;
70 }
71 for (i = 0; i < len; i++) to[i] = locase(dir: hpfs_sb(sb: s)->sb_cp_table,a: from[i]);
72 return to;
73}
74
75int hpfs_compare_names(struct super_block *s,
76 const unsigned char *n1, unsigned l1,
77 const unsigned char *n2, unsigned l2, int last)
78{
79 unsigned l = l1 < l2 ? l1 : l2;
80 unsigned i;
81 if (last) return -1;
82 for (i = 0; i < l; i++) {
83 unsigned char c1 = upcase(dir: hpfs_sb(sb: s)->sb_cp_table,a: n1[i]);
84 unsigned char c2 = upcase(dir: hpfs_sb(sb: s)->sb_cp_table,a: n2[i]);
85 if (c1 < c2) return -1;
86 if (c1 > c2) return 1;
87 }
88 if (l1 < l2) return -1;
89 if (l1 > l2) return 1;
90 return 0;
91}
92
93int hpfs_is_name_long(const unsigned char *name, unsigned len)
94{
95 int i,j;
96 for (i = 0; i < len && name[i] != '.'; i++)
97 if (no_dos_char(c: name[i])) return 1;
98 if (!i || i > 8) return 1;
99 if (i == len) return 0;
100 for (j = i + 1; j < len; j++)
101 if (name[j] == '.' || no_dos_char(c: name[i])) return 1;
102 return j - i > 4;
103}
104
105/* OS/2 clears dots and spaces at the end of file name, so we have to */
106
107void hpfs_adjust_length(const unsigned char *name, unsigned *len)
108{
109 if (!*len) return;
110 if (*len == 1 && name[0] == '.') return;
111 if (*len == 2 && name[0] == '.' && name[1] == '.') return;
112 while (*len && (name[*len - 1] == '.' || name[*len - 1] == ' '))
113 (*len)--;
114}
115

source code of linux/fs/hpfs/name.c